It is oftentimes desired that a particular part, or piece, be formed from materials that must be mixed prior to piece formation. This can occur, for example, where two liquid state components are mixed and, after mixing, cured to assume a solid state with the part being formed usually in a mold having the desired contour, the mixture commonly then being retained in the mold until curing has progressed sufficiently such that the formed part has sufficient rigidity to retain the desired shape without mold assistance. Where the components are those necessary to form a polyurethane part, mixing of the components and forming of the part must occur rapidly since curing progresses quite swiftly after the components are mixed.
Since the achieved mixture determines the product and quality thereof, it is, of course, necessary that not only must a system be provided for rapid handling of the mixed materials, the materials must be metered, or proportioned, as accurately as possible each time a piece is formed.
While heretofore known and/or utilized devices have provided systems for mixing materials and forming a piece of desired contour from mixed materials, such devices have not proved to be completely successful in providing a system for rapid handling of materials and/or achieving dependable metering of the desired amounts of materials relative to each other as is necessary to achieve quality of product.
In addition, where mixtures that are difficult to handle are concerned, such as polyurethane, the devices now known and/or utilized have not proved to be capable of handling such materials in an entirely satisfactory manner, particularly where the piece to be formed had unusual characteristics, such as, for example, being relatively large in size and/or having windows to be formed therein. Heretofore known and/or utilized devices have, for example, not been capable of mixing adequate amounts of materials in sufficient time and/or require the use of small orifices and high pressures for metering and delivery of materials.